Arctic methane catastrophe scenario is based on new empirical observations @the_ecologist

"Those who understand Arctic seabed geology and the oceanography of water column warming from ice retreat do not say that this is a low probability event. I think one should trust those who know about a subject rather than those who don't. As far as I'm concerned, the experts in this area are the people who have been actively working on the seabed conditions in the East Siberian Sea in summer during the past few summers where the ice cover has disappeared and the water has warmed. The rapid disappearance of offshore permafrost through water heating is a unique phenomenon, so clearly no 'expert' would have found a mechanism elsewhere to compare with this... I think that most Arctic specialists would agree that this scenario is plausible."